Typewriter line space mechanism



Feb. 18, 1969 J. P. BVARKDOLL 3,423,150

TYPEWRITER LINE SPACE MECHANISM Filed Nov. 26, 1965 Sheet of 5 92 Q 98 INVENTOR.

, 32 JOSEPH P. BARKDOLL BY E .1 5.4 M115,

AGENT Feb. 18, 1969 J. P. BARKDOLL TYPEWRITER LINE SPACE MECHANISM Sheet Filed Nov. 26, 1965 AGENT Feb. '18, 1969 .1. P. BARKDOLL 3,423,150

TYPEWRITER LINE SPACE MECHANISM Filed Nov. 26, 1965 Sheet 3 INVENTOR.

JOSEPH P. BARKDQLL AGENT United States Patent 3,428,160 TYPEWRIT ER LINE SPACE MECHANISM Joseph P. Barkdoll, Sun City Center, Fla., assignor to SCM Corporation, New York, N.Y., a corporation of New York Filed Nov. 26, 1965, Ser. No. 509,807

U.S. Cl. 197-114 Int. Cl. B413 19/94, 19/68, 19/90 3 Claims ABSTRACT OF THE DISCLOSURE Background of the invention A conventional power operated line spacing mechanism has a line space pawl that engages a platen ratchet and vertically spaces the platen with a sudden, relatively heavy thrust from the power source and that is driven into a solid abutment with the same heavy thrust for stopping the platen spacing. This mechanism has definite disadvantages over the present improved mechanism. One disadvantage is that it requires an excessive number of parts to perform line spacing which results in excessive costs. Another disadvantage is that these parts must be extraordinarily rigidly designed to withstand the shock of stopping the line spacing action which results in additional excessive costs. Still another and particularly imlportant disadvantage is the highly undesirable noise caused by the pawl stopping against the solid abutment.

A patent, 2,288,828, issued to J. Mueller on July 7, 1942, discloses a line spacing mechanism that partially overcomes these disadvantages by having a rotatably driven linkage for vertically spacing the platen which eliminates the need for a solid abutment to stop the platen spacing. This mechanism has the disadvantage of having an excessive number of parts to perform the line spacing.

A patent, 2,667,256, issued to B. F. Madsen on Jan. 26, i954, discloses a line spacing mechanism that overcomes the above mentioned disadvantages by having a rotatably driven line space pawl directly engage a ratchet for indexing the platen. This mechanism is limited for use in a non-movable carriage machine such as teletype machines and, therefore, it is not applicable for movable carriage machines such as conventional typewriters.

A patent, 2,728,438, issued to D. G. Balfour on Dec. 27, 1955, discloses a line spacing mechanism that is operable to vertically space the platen without moving the carriage and irrespective of the position of the carriage. This mechanism has a disadvantage in that it requires a completely additional mechanism to the conventional combination line spacing carriage return mechanism.

The object of this invention is to provide a quietly and efficiently operable line spacing mechanism for conventional movable carriage machines.

Another object of this invention is to provide a line spacing mechanism having a smoothly accelerating and decelerating motion during the spacing operation.

Another object of this invention is to provide a simplified rotatably driven line spacing mechanism for conventional movable carriage machines.

Another object of this invention is to provide a simplified rotatably driven line spacing mechanism that is oper- 3,428,160 Patented Feb. 18, 1969 "ice able to vertically space the platen without moving the carriage irrespective of the position of the carriage.

Still another object of this invention is to provide a simplified rotatably driven line spacing mechanism that is operable for automatic repetitive vertical spacing of the platen without moving the carriage and irrespective of the position of the carriage.

A further object of this invention is to provide a simplified rotatably driven line spacing mechanism that is operable by the carriage return function.

Another object of this invention is to provide a simlified rotatably driven line spacing mechanism for conventional movable carriage machines which includes means for holding the ratchet engaging member free from the ratchet during the return portion of a spacing operation.

Other objects and further novel features of the present invention will become more fully apparent from the appended claims and as the ensuing detailed description and discussion proceeds in conjunction with the accompanying drawing, in which:

FIGURE 1 is a partial plan view of a typewriter showing the orientation of the line spacing mechanism, the carriage return mechanism, and the key-board controlling keys;

FIGURE 2 is a front perspective view showing the power operated line spacing mechanism and a power operated carriage return mechanism, of the present invention;

FIGURE 3 is an enlarged portion of FIGURE 2 of the selectively operable means for effecting the line spacing operation;

FIGURE 4 is an enlarged back elevational view of the carriage mounted line space member supporting assemy;

FIGURE 5 is an enlarged right side elevational view showing the line space member in its normal inoperative position;

FIGURE 6 is a view similar to FIGURE 5 but instead showing the line space member near the midway of its spacing operation; and

FIGURE 7 is a view similar to FIGURE 5 but instead showing the line space member at the end of its line spacing operation.

Referring now to the drawing, FIGURE 1 illustrates a typewriter having side frames 10, a movable carriage 12 supported by the side frames 10 with a platen 14 rotatably mounted thereon and feed rolls 15 (FIGURE 2) for advancing a work sheet around platen 14, a rotatable power drive train 16, a carriage supported rotatable line spacing mechanism 18, a selectively operable means 20 for coupling drive train 16 to mechanism 18, a carriage return mechanism 22 (FIGURE 1), a keyboard control key 24 for actuating the line space mechanism 18 and a keyboard control key 26 for actuating the carriage return mechanism 22. Referring to FIGURE 2, this simplified line spacing mechanism 18 includes a rectangularly shaped shaft 30 rotatably supported on the carriage 12, an actuator 32 rigidly assembled to the left end of shaft 30 and the line space member 34 having one end pivotally connected to actuator 32 and the other end engageable with a platen ratchet 36. Depression of key 24 or key 26 releases means 20 for a single revolution which rotates actuator 32 a single revolution causing line space member 34 to engage ratchet 36 and vertically space the platen 14. The motion of member 34 accelerates during the first platen spacing portion of the rotating actuator 32 and decelerates during the remainder platen spacing portion which substantially stops the platen 14 before member 34 disengages ratchet 36, there- 0 by providing a smooth and quiet line spacing operation for a movable work sheet supporting carriage machine. Referring now particularly to FIGURES 2 and 3. The

depression of key 24 pulls link forward by a conventional linkage (not shown). Link 40 is connected to an arm 42 which is pivotally mounted on a shaft 44. A trigger 46 is pivotally mounted on arm 42 by a shouldered pin 48. A spring 50 has one end connected to trigger 46 and the other end connected to arm 42 which biases trigger 46 clockwise to a limited position determined by the trigger 46 abutting against a latch 52. Latch 52 is pivotally mounted on shaft 44 and is biased clockwise by a spring 54 to a limited position determined by a finger 56 extending from latch 52 abutting againsta rigid bracket (not shown). A tab 58 formed from latch 52 normally engages an end 60 formed for a clutch spring 62 thereby holding spring clutch 62 slightly expanded and therefore disengaged from a driving hub 64. Hub 64 is rigidly assembled to a power driven shaft 66 by a set screw 68. A driven hub 70 is rotatably supported by shaft 66 and is engaged by the opposite end of spring clutch 62. Since the spring clutch 62 is normally disengaged from driving hub 64, driven hub 70 is idle. A

pulley 72 is rigidly assembled to hub 70.

The :forward movement of link 40 pivots arm 42 counter-clockwise about shaft 44 which causes trigger 46 to pivot latch 52 counter-clockwise about shaft 44 which, in turn, pulls tab 58 off from spring clutch end 60. Spring clutch '62 now tightens on hub 64 which positively clutches driving hub 64 to driven hub 70. The rotatable power drive train 16 includes a motor 74, a small diameter pulley (not shown) rigidly assembled to the motor shaft, a larger diameter pulley 76 rigidly assembled on shaft 66 and a belt 78 connecting motor 74 to pulley 76. When motor 74 is energized, shaft 66 is rotated clockwise, and since spring clutch 62 has been released, pulley 72 is also rotated clockwise.

A bracket 80 is rigidly supported on a frame member (not shown) having a bearing 82 rotatably supported thereby. A pulley 84 is rigidly assembled to bearing 82 and a timing belt 86 interconnects pulley 72 and pulley 84. The rectangular shaft 30 extends through a similarly shaped aperture in bearing 82 in such a manner that the shaft 30 is free to slide longitudinally through bearing 82 whenever the carriage 12 is moved and that the shaft 30 will rotate whenever the bearing 82 is rotated by pulley 84. The extreme right end of shaft 30 is supported by a flexible member which is flexible to prevent the shaft 30 from binding by the left, center and right supporting means. A spring biased idler roller 88 is pivotally assembled to bracket 80 for maintaining a predetermined tautness to belt 86. The clockwise rotation of pulley 72 rotates pulley 84 clockwise which, in turning rotates shaft 30 clockwise.

Referring now to FIGURE 4, shaft 30 is adjustably supported in a bearing 90 which is rotatably mounted in a bracket 92. Bracket 92 is rigidly supported on the upper carriage bed 93 which supports the movable carriage 12 with respect to the lower rigid carriage bed 94 (FIGURE 2). Bearing 90 (FIGURE 4) is held in axial alignment on one side by a keeper 95 and on the opposite side by a shouldered portion abutting against bracket 92. Shaft 30 is adjustable relative to bearing 90 by actuator 32 being rigidly assembled to bearing 90 and by an adjuster plate 96 being rigidly assembled to shaft 30 and 'by plate 96 being adjustable with respect to actuator 32 by screw 98. With screw 98 loose, shaft 30 and plate 96 can be adjusted relative to bearing 90 and actuator 32. With line space member 34 pivotally mounted on a carrier 100 which is rigidly assembled to actuator 32, member 34 is thereby adjusted relative to shaft 30 for positioning pin 112 relative to teeth of ratchet 36.

As viewed in FIGURE 5, a spring 102 having one end connected to carrier 100 and the other end connected to a post 104 which is rigidly assembled on the carriage frame 106 biases member 34 upward to its normal inoperative position. The upper end of member 34 has a slotted opening 108 (FIGURE 2) sufiiciently wide to receive the teeth 110 of ratchet 36 and has a pin 112 rigidly assembled thereto and extending parallel with the axis of the platen 14 through opening 108 and beyond member 34 to extend over a cam surface 114 of an adjustable line space lever 116. Lever 116 is pivotally mounted on a shouldered stud 118 which is rigidly assembled on carriage end frame 106. A detent 120 is pivotally mounted on a shouldered stud 122, which is rigidly assembled to frame 106 and has a pin 124 rigidly assembled thereto near its free end. A spring 126 having one end connected to detent 120 and the other end connected to stud 118 biases pin 124 in one of three similar notches 128 formed in the outer edge of lever 116.

As shown in FIGURE 5, lever 116 is positioned to provide for a three increment line spacing operation, better known as a triple line space. An car 130 formed from detent 120 extends through an elongated aperture 132 in lever 116 and abuts against one end for limiting the movement of lever 116 toward the right. A spring 134 having one end connected to member 34 near pin 112 and the other end connected to a spring anchor 136 which is rigidly assembled to frame 106 biases pin 112 against surface 114 of lever 116 when member 34 is in its normal inoperative position and biases pin 112 into engagement with ratchet teeth 110 during a line space operation. A detent 138 is pivotally mounted on a shouldered screw 140 and is biased clockwise by a spring 142 which has one end connected to detent 138 and the other end connected to a spring anchor 144. A roller 146 is pivotally supported by detent 138 and is normally biased in a position between two adjacent teeth 110 which holds the platen 12 in a fixed position for a line of typing.

Referring back to FIGURES 2 and 3, as previously explained, latch 52 may release spring clutch 62 and the rotation of shaft 66 now rotates pulley 72 clockwise. An extension 150 extending from pulley 72 moves upward by the rotating pulley 72 to contact and pivot trigger 46 counter-clockwise which releases latch 52. Spring 54 now biases latch 52 clockwise which positions tab 58 in the path of clutch spring end 60. As pulley 72 continues to rotate, spring clutch 62 is expanded by tab 58 which disengages pulley 72 from the driving shaft 66 thereby providing a cyclically single revolution for a normal line spacing operation. Since latch 52 is released by extension 150, key 24 can be held depressed without repeating the cycle. This single revolution of pulley 72 rotates pulley 84 a single revolution via belt 86. Pulley 84 and bearing 82 rotate shaft 30 a single revolution in a clockwise direction.

Referring now to FIGURES 5, 6 and 7, during the revolution of shaft 30, actuator 32 starts to rotate counter-clockwise and pulls pin 112 of line space member 34 off surface 114 of lever 116 and into engagement with a ratchet tooth 110. During approximately the first half of the platen spacing portion of the cyclically rotatable actuator 32, the line space member 34 and therefore, the ratchet and platen assembly are accelerated from a rest position as shown in FIGURE 5 to a maximum accelerated position as shown in FIGURE 6. During the remaining half of the platen spacing portion of the rotatable actuator 32, the line space member 34 and the ratchet and platen assembly are decelerated from the maximum accelerated position as shown on FIGURE 6 to a substantially rest position as shown in FIGURE 7. At this point, member 34 contacts post 104 and as the actuator 32 goes beyond the decelerated position of FIG- URE 7, pin 112 is driven outward and disengaged from the ratchet teeth 110. The force of spring 142 biases the detent roller 146 between two ratchet teeth 110 for accurately positioning and holding the platen assembly for the new line of typing. This decelerating platen spacing motion eliminates the need of the rigid abutment line space stopping means as used by conventional line spacing mechanisms which eliminates the undesirable noise, reduces manufacturing costs and provides a more efficient line spacing mechanism. As actuator 32 continues to move counter-clockwise through the remaining portion of its cycle from the position in FIGURE 7 to the position shown in FIGURE 5 carrying member 34 in a path to contact post 104 which lifts member 34 out of the path of the ratchet teeth 110 until pin 112 is repositioned on surface 114 of lever 116. By holding line space member 34 out of the path of ratchet 36 during the return motion further adds to the quieter operation of the present invention over the prior art since the prior conventional line space pawls are biased to ratchet against the teeth on the return motion resulting in a clicking noise.

To vary the number of vertical space increments for each line space operation, lever 116 is moved toward the left (FIGURE 5) for either a double or single line space which varies the distance that pin 112 rides along surface 114.

The selectively operable means 20 includes a means for automatically repeating the cyclical line space operation. By depressing key 24 to a depth beyond the normal single operation depth, a finger 152 at the upper end of arm 42 contacts an car 154 extending from latch 52 and pivots latch 52 counter-clockwise a suflicient distance to pull tab 58 out of the path of spring clutch end 60 and to hold tab 58 in this position which allows the spring clutch 62 to continue cycling thereby automatically repeating the line space operation. When key 24 is released, spring 54 biases latch 52 clockwise which positions tab 58 in the path of spring clutch end 60 for engaging end 60 and expanding spring clutch 62 for disengaging the rotating power shaft 66 from pulley 72. Since shaft 30 is slidable through bearing 82 as the carriage 12 is moved either to the right or to the left, and since key 24 is directly connected to the seelctively operable means 20, the platen 14 can be vertically line spaced without moving the carriage 12 and irrespective of the position of the carriage 12.

This power operated line spacing mechanism is also operable in combination with a carriage return mechanism 22. By depressing carriage return key 26, a link 160 is pulled forward by a conventional linkage not shown). Link 160 is connected to an actuator 162 which is pivoted counter-clockwise about shaft 44 to engage and energize a spring clutch 164. The power of rotating shaft 66 is now coupled to rotate a carriage return drum 166. A cord 168 having several turns around drum 166 has one end 170 connected to the right carriage end (not shown) and has the other end 172 connected to the left carriage end 106. Rotating drum 166 clockwise returns the carriage 12 to the left margin position. Actuator 162 has an arm 174 extending toward the left and positioned adjacent a tab 176 extending from the lower end of arm 42. The first position of the counter-clockwise motion of actuator 162 causes arm 174 to contact tab 176 and pivot arm 42 which in turn pivots latch 52 counter-clockwise which again releases spring clutch end '60 for cyclically operating the line space mechanism 18.

It can now be seen that this novel power operated line spacing mechanism for movable carriage machines is quiet, eflicient and substantially simplified over the prior art by utilizing a rotary actuated line spacing mechanism and having a cyclically operable rotary actuator 32 supported on the movable carriage 12 and directly connected to the line space member 34.

What is claimed and desired to be secured by Letters Patent is:

1. In a typewriter or the like having a carriage and a platen rotatably mounted thereon comprising:

(a) a rotatable power source (16);

(b) a shaft (30) supported on the carriage;

(c) means (72, 86, 84, 82) including a platen spacing clutch (20) selectively operable to couple said power source to said shaft for rotating said shaft a single revolution;

((1) an actuator (32) supported on the carriage and rigidly connected to said shaft for rotating a single revolution about the axis of said shaft (30) in response to the rotation of said shaft (30); and

(e) a member (34) pivotally supported on said actuator (32) at a point spaced from the axis of said actuator (32) and operable by said actuator from a platen disengaged position to engage and vertically space the platen during a portion of the revolution of said actuator for imparting an acceleration and deceleration movement to the platen and to return to said disengaged position during the remaining portion of the revolution of said actuator.

2. A typewriter as defined in claim 1 further comprising a rigid abutment (104) spaced from the platen and located to be contacted by said member (34) to hold said member out of engagement from the platen during the return portion of the cyclic movement of said memher.

3. A typewriter as defined in claim 2 further comprising a spring (134) connected to said member (34) for biasing said member (34) into platen engagement during the platen spacing portion of the cycle and for biasing said member (34) against said abutment (104) during the return portion of the cycle.

References Cited UNITED STATES PATENTS 1,081,108 12/1913 Friedman 197-65 1,094,432 4/ 1914 Friedman 197-114 1,283,596 11/1918 Thieme 197-114 1,469,776 10/1923 Crawley 197-114 2,153,182 4/1939 Gray 197-114 2,766,826 10/ 1956 Osgood 197-114 X 2,791,311 5/1957 Yerks et al. 197-114 2,885,053 5/ 1959 Davidson 197-114 X 2,902,133 9/1959 Walton et a1. 197-66 3,017,980 1/1962 DOnofrio 197-114 3,031,057 4/1962 Williams 197-114 2,905,297 9/ 1959 Stuiber et al. 197-91 X 2,973,078 2/1961 Templeton et al. 197-17 3,212,616 10/ 1965 Frechette et al. 197-82 ROBERT E. PULFREY, Primary Examiner. E. T. WRIGHT, Ir., Assistant Examiner.

US. Cl. X.R. 197-65, 

